Multilayer wiring board and its manufacturing method

ABSTRACT

A multilayer wiring board having a plurality of wiring boards in which wiring layers and resin layers in each wiring board are alternately arranged in a laminated formation. In the multilayer wiring board, all the resin layers and the wiring layers, except a resin layer in the plurality of wiring boards, are separated in a same position between the plurality of wiring boards and the resin layer is continuous in the same position.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a divisional application of U.S. application Ser. No. 11/180,780filed on Jul. 14, 2005, which and claims priority of Japanese PatentApplication Number 2005-105232, filed on Mar. 31, 2005, both of whichare hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to a multilayer wiring board andits manufacturing method, and more particularly to a coreless interposerboard and its manufacturing method in which a plurality of resin layersand a plurality of wiring layers are alternately arranged in laminatedformation.

2. Description of the Related Art

In recent years, development of SIP (System In Package) of various typesis carried out in order to meet the demands for high-speed, high-densityLSI packages. SIP is a kind of the technology for incorporating two ormore semiconductor chips to a single semiconductor package. Developmentof an interposer board on which two or more semiconductor chips arecarried is also briskly performed with the development of SIP.

For example, the interposer board is a wiring board in which wiringlayers made of metal, such as copper, and insulating layers made ofresin, such as an epoxy or polyimide resin, are laminated alternately.

Usually, a plurality of interposer boards are formed in a comparativelylarge base board collectively, and thereafter a dicing process isperformed to cut the base board into the respective interposer boards.

Japanese Laid-Open Patent Application No. 10-027971 discloses thecutting process of an organic thin-film multilayer wiring board in orderfor preventing the removal of the organic thin film from the substrateafter cutting and the cleavage of the substrate after cutting.

Japanese Laid-Open Patent Application No. 10-135157 discloses themultilayer wiring board and its manufacturing method in order forpreventing the removal of the interlayer insulation film in a dicingprocess.

In the conventional methods mentioned above, it is necessary to cutmechanically the resin layers for which the laminated formation iscarried out with a dicing blade etc. By the external force applied inthe dicing process, the resin layers for which the laminated formationis carried out may be damaged, or the film removal may occur in theinterface of the respective resin layers.

FIG. 28 shows the composition of a conventional multilayer wiring board.The multilayer wiring board 20 of FIG. 28 is a multilayer wiring boardon which a plurality of wiring boards (in this example, two pieces) arearranged sidewise, and the first through fourth resin layers 1-4 and thefirst through fourth wiring layers 5-8 in each wiring board arelaminated alternately and these layers do not have a core substrate.

When the multilayer wiring board 20 is cut into the respective wiringboards, the cutting area 9 indicated by the dotted line in FIG. 28 ismechanically cut with a dicing blade.

In the case of the multilayer wiring board 20 of FIG. 28, all the resinlayers 1-4 are mechanically cut by the dicing blade. In the mechanicalcutting, all the resin layers tend to be damaged, and the removal ofeach resin layer in the interface easily occurs.

Even if the removal of the resin layer in the resin interface at thetime of cutting is avoided, there is the problem that reliability of therespective wiring boards deteriorates due to the resin damage at thetime of cutting.

In order to avoid the problem, for example, Japanese Laid-Open PatentApplication No. 10-027971 proposes the method of cutting mechanicallythe multilayer wiring board with a dicing blade after the resin layersare removed by a laser beam cutting.

However, in the proposed method of Japanese Laid-Open Patent ApplicationNo. 10-027971, the protection of the cross-section of the resin layersat the time of cutting mechanically is not taken into consideration.Moreover, the introduction of the laser machine for cutting the resinlayers, the increase in the manufacturing processes needed, etc. arenecessary, which will raise the cost. Thus, the proposed method is notfeasible in the actual production line.

On the other hand, the proposed method of Japanese Laid-Open PatentApplication No. 10-135157 is effective for the multi-layer wiring boardhaving the core substrate on which the resin layers and the wiringlayers are held.

However, in the case of the coreless wiring board in which all thelayers are formed of resin and which does not have a core substrate, itcannot be said that the proposed method of Japanese Laid-Open PatentApplication No. 10-135157 provides adequate effects of preventing theremoval of the interlayer insulation film when cutting mechanically thewiring board.

SUMMARY OF THE INVENTION

An object of the present invention is to provide an improved multilayerwiring board in which the above-mentioned problems are eliminated.

Another object of the present invention is to provide a multilayerwiring board which is highly reliable and excellent in the electricalproperties by reducing or avoiding the resin removal and damage at thetime of mechanical cutting.

Another object of the present invention is to provide a manufacturingmethod of a multilayer wiring board which is highly reliable andexcellent in the electrical properties by reducing or avoiding the resinremoval and damage at the time of mechanical cutting.

In order to achieve the above-mentioned objects, the present inventionprovides a multilayer wiring board which comprises: a plurality ofwiring boards in which wiring layers and resin layers in each wiringboard are alternately arranged in a laminated formation, wherein all theresin layers and the wiring layers, except a resin layer in theplurality of wiring boards, are separated in a same position between theplurality of wiring boards and the resin layer is continuous in the sameposition.

In order to achieve the above-mentioned objects, the present inventionprovides a manufacturing method of a multilayer wiring board having aplurality of wiring boards in which wiring layers and resin layers ineach wiring board are alternately arranged in a laminated formation, themanufacturing method comprising steps of: forming a first resin layerand a first wiring layer on a supporting board; forming a second resinlayer and a second wiring layer on the first resin layer; forming two ormore additional resin layers and two or more additional wiring layers onthe second resin layer alternately so that all the resin layers and thewiring layers, except a resin layer in the plurality of wiring boards,are separated in a same position between the plurality of wiring boards;and removing the supporting board.

In the multilayer wiring board of the present invention, the cuttingarea where the multilayer wiring board is cut into the respective wiringboards is constituted by only one resin layer. The exposed resin layersamong the plurality of resin layers are the top layer and the bottomlayer only, and other resin layers are not exposed.

In order to absorb the damage to the resin layers at the time ofmechanical cutting, the cutting area is provided as the structurallyweak layer. The resin layer being cut is made thinner, and the cuttingof the multilayer wiring board itself is made easy.

Moreover, in the multilayer wiring board of the present invention, theresin cutting plane is covered with a metal film in order to protect theresin cutting plane. The grounding of each wiring layer is connectedwith a metal film. The multilayer wiring board of the present inventionis configured so that all the laminated resin layers are not cut, butall the resin layers, except the resin layer being cut, are evacuatedfrom the cutting area beforehand.

By this composition, it is possible to avoid the removal of the resinlayer by the external force at the time of mechanical cutting. Bypreventing the exposure of the end face of each of the plurality oflaminated resin layers, it is possible to reduce the damage to thelaminated resin surface at the time of mechanical cutting, and thereliability is improved.

Moreover, in order to reduce the damage to the main part of theinterposer board, the cutting area is provided as the structurally weaklayer. The resin layer being cut is made thinner, and the cutting of themultilayer wiring board itself is made easy. By lowering the forceexerting on the resin layer itself, the damage to the interposer boardcan also be reduced.

Moreover, the damage to the cross-section (end face) of the laminatedresin layers at the time of mechanical cutting is prevented by coveringthe laminated resin layers with a metal film. In addition, themechanical strength in the removing direction can also be raised withthe metal film interconnecting the edges of the top and bottom resinlayers. It is possible to also raise the reliability. Further, theelectrical properties can also be raised by connecting the groundterminals of the wiring layers mutually.

According to the multilayer wiring board and its manufacturing method ofthe present invention, the damage at the time of mechanical cutting canbe reduced, and it is possible to provide the interposer board whosereliability and electrical properties are raised.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects, features and advantages of the present invention will beapparent from the following detailed description when read inconjunction with the accompanying drawings.

FIG. 1A and FIG. 1B are cross-sectional views showing the composition ofa multilayer wiring board in one embodiment of the present invention.

FIG. 2A and FIG. 2B are cross-sectional views showing the composition ofmodifications of the multilayer wiring board of FIG. 1A.

FIG. 3 is a cross-sectional view showing the composition of amodification of the multilayer wiring board of FIG. 1A.

FIG. 4A and FIG. 4B are cross-sectional views showing the composition ofa multilayer wiring board in another embodiment of the presentinvention.

FIG. 5A, FIG. 5B, FIG. 5C, FIG. 5D and FIG. 5E are cross-sectional viewsshowing the composition of modifications of the multilayer wiring boardof FIG. 4A.

FIG. 6A and FIG. 6B are cross-sectional views showing the composition ofa multilayer wiring board in another embodiment of the presentinvention.

FIG. 7A and FIG. 7B are cross-sectional views showing the composition ofmodifications of the multilayer wiring board of FIG. 6A.

FIG. 8A and FIG. 8B are diagrams showing the composition of amodification of the multilayer wiring board of FIG. 6A.

FIG. 9 is a cross-sectional view showing the composition of amodification of the multilayer wiring board of FIG. 8A.

FIG. 10A and FIG. 10B are cross-sectional views showing the compositionof a multilayer wiring board in another embodiment of the presentinvention.

FIG. 11A, FIG. 11B, FIG. 11C, FIG. 11D and FIG. 11E are diagrams forexplaining the manufacturing method of the multilayer wiring boardconcerning the embodiment of FIG. 1A.

FIG. 12A, FIG. 12B, FIG. 12C, FIG. 12D and FIG. 12E are diagrams forexplaining the manufacturing method of the multilayer wiring boardconcerning the embodiment of FIG. 2A.

FIG. 13A, FIG. 13B, FIG. 13C, FIG. 13D and FIG. 13E are diagrams forexplaining the manufacturing method of the multilayer wiring boardconcerning the embodiment of FIG. 3A.

FIG. 14A, FIG. 14B, FIG. 14C and FIG. 14D are diagrams for explainingthe manufacturing method of the multilayer wiring board concerning theembodiment of FIG. 4A.

FIG. 15A, FIG. 15B, FIG. 15C and FIG. 15D are diagrams for explainingthe manufacturing method of the multilayer wiring board concerning theembodiment of FIG. 5A.

FIG. 16A, FIG. 16B, FIG. 16C and FIG. 16D are diagrams for explainingthe manufacturing method of the multilayer wiring board concerning theembodiment of FIG. 6A.

FIG. 17A, FIG. 17B, FIG. 17C and FIG. 17D are diagrams for explainingthe manufacturing method of the multilayer wiring board concerning theembodiment of FIG. 7A.

FIG. 18A, FIG. 18B, FIG. 18C and FIG. 18D are diagrams for explainingthe manufacturing method of the multilayer wiring board concerning theembodiment of FIG. 8A.

FIG. 19A, FIG. 19B, FIG. 19C and FIG. 19D are diagrams for explainingthe manufacturing method of the multilayer wiring board concerning theembodiment of FIG. 9A.

FIG. 20A, FIG. 20B, FIG. 20C and FIG. 20D are diagrams for explainingthe manufacturing method of the multilayer wiring board concerning theembodiment of FIG. 10A.

FIG. 21A, FIG. 21B, FIG. 21C and FIG. 21D are cross-sectional viewsshowing the composition of the interposer boards which are produced bycutting the multilayer wiring boards of FIG. 1A, FIG. 1B, FIG. 2A andFIG. 3, respectively.

FIG. 22A, FIG. 22B, FIG. 22C, FIG. 22D and FIG. 22E are cross-sectionalviews showing the composition of the interposer boards which areproduced by cutting the multilayer wiring boards of FIG. 4A, FIG. 5B,FIG. 5C, FIG. 5D and FIG. 5E, respectively.

FIG. 23A and FIG. 23B are cross-sectional views showing the compositionof the interposer boards which are produced by cutting the multilayerwiring boards of FIG. 6A and FIG. 6B, respectively.

FIG. 24A and FIG. 24B are cross-sectional views showing the compositionof the interposer boards which are produced by cutting the multilayerwiring boards of FIG. 7A and FIG. 7B, respectively.

FIG. 25A, FIG. 25B and FIG. 25C are cross-sectional views showing thecomposition of the interposer board which is produced by cutting themultilayer wiring boards of FIG. 8A, FIG. 8B and FIG. 9, respectively.

FIG. 26 is a cross-sectional view showing the composition of aninterposer board to which the multilayer wiring board of the presentinvention is applied.

FIG. 27 is a cross-sectional view showing the composition of asemiconductor device in which the interposer board to which themultilayer wiring board of the invention is applied is mounted on themounting board.

FIG. 28 is a cross-sectional view showing the composition of aconventional multilayer wiring board.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

A description will now be given of the preferred embodiments of theinvention with reference to the accompanying drawings.

FIG. 1A and FIG. 1B show the composition of the multilayer wiring boardin one embodiment of the invention.

For the sake of convenience, a different hatching is given to show eachof the first through fourth resin layers 1-4 in the embodiment of FIG.1A and FIG. 1B, but each layer is made of the same resin material.

In the multilayer wiring board 10 of FIG. 1A, the two wiring boards arearranged in which the laminated formation of each wiring board isperformed so that the plurality of resin layers (namely, the first resinlayer 1, the second resin layer 2, the third resin layer 3 and thefourth resin layer 4) and the plurality of wiring layers (namely, thefirst wiring layer 5, the second wiring layer 6, the third wiring layer7 and the fourth wiring layer 8) are alternately arranged, and eachlayer does not have a core substrate. In order to cut the multilayerwiring board 10 into the respective wiring boards, the wiring boards inthe multilayer wiring board 10 of this embodiment are continuouslyinterconnected by the first resin layer 1 only.

Similarly, in the multilayer wiring board 10 of FIG. 1B, the two wiringboards are arranged in which the laminated formation of each wiringboard is performs so that the first through fourth resin layers 1-4 andthe first through fourth wiring layers 5-8 are alternately arranged, andeach layer does not have a core substrate. In order to cut themultilayer wiring board 10 into the respective wiring boards, the wiringboards in the multilayer wiring board 10 of this embodiment arecontinuously interconnected by the third resin layer 3 only.

For example, in the multilayer wiring board 10 of FIG. 1A, only thefirst resin layer 1 is cut to produce the two wiring boards, and theother resin layers 2-4 among the plurality of resin layers 1-4 areformed so that they are evacuated from the cutting area 9, respectively.

As mentioned above, in the conventional multilayer wiring board of FIG.28, all the resin layers are cut to produce the two wiring boards, andall the resin layers may be damaged at the time of cutting.

In contrast, in the present embodiment, only one resin layer is cut andthe two wiring boards are produced, and it is possible to reduce thedamage of the plurality of resin layers at the time of cutting.

Moreover, in the multilayer wiring board 10 of FIG. 1B, the third resinlayer 3 which is formed to be continuous with the intermediate resinlayer among the resin layers 1-4 of each wiring board has a raisedportion in the cutting area 9 between the two wiring boards, and thisraised portion is flush with the outside resin layer 1. And only thethird resin layer 3 is cut at the raised portion to produce the twowiring boards, and the other resin layers 1, 2 and 4 among the pluralityof resin layers 1-4 are formed so that they are evacuated from thecutting area 9, respectively.

In this embodiment, the thickness of each of the resin layers 1-4 isabout 4-6 micrometers, and the thickness of each of the wiring layers5-8 is about 3-8 micrometers. The resin layers 1-4 are made of any of apolyimide resin, a phenol resin, an epoxy resin, a silicon-based resinand BCB, and the wiring layers 5-8 are made of any of copper (Cu),nickel (Ni) and gold (Au), solely or in combination.

In FIG. 1A and FIG. 1B, the cutting area 9 is provided to show theportion where the multilayer wiring board 10 is cut into the respectivewiring boards. For example, when the width of a dicing blade used forcutting is about 150 micrometers, the width of the cutting area 9 isabout 200 micrometers.

FIG. 26 shows the composition of an interposer board to which themultilayer wiring board of the present invention is applied.

In the interposer board 30 shown in FIG. 26, the capacitor 31 and theinductor 32 are formed inside the wiring boards which are produced bycutting the multilayer wiring board 10.

In each of the wiring boards, the laminated formation of the firstthrough fourth resin layers 1-4 is performed, and each wiring board isprovided with the cross-section where only the first resin layer 1 iscut at the dicing process. Therefore, the damage at the time of cuttingof the multilayer wiring board 10 can be reduced, and it is possible toprovide the structure of an interposer board with the reliability andelectrical properties being raised.

FIG. 27 shows the composition of a semiconductor device in which theinterposer board to which the multilayer wiring board of the inventionis applied is mounted on the mounting board.

In the semiconductor device 40 shown in FIG. 27, the composition of amulti-chip module is provided in which the semiconductor chip 43 (thefirst chip) and the semiconductor chip 44 (the second chip) are mountedon the mounting board 41 through the interposer board 30. In this case,the interposer board 30 has the same composition as the interposer board30 of FIG. 26.

In this semiconductor device 40, each of the semiconductor chips 43 and44 is fixed to the interposer board 30 via the under-fill 47. Thesemiconductor chip 43 and the semiconductor chip 44 are connected to theelectrode pads on the interposer board 30 through the solder bumps 46which are formed on the bottom surface of each of the semiconductorchips 43 and 44.

The interposer board 30 is fixed to the mounting board 41 via theunder-fill 49. The solder bumps 42 are formed on the bottom surface ofthe mounting board 41, and this semiconductor device 40 is furthermounted on the mother board (not illustrated).

Next, FIG. 2A and FIG. 2B show the composition of modifications of themultilayer wiring board of FIG. 1A.

In the embodiment of FIG. 2A and FIG. 2B, only the top resin layer 1 andthe bottom resin layer 4 are exposed to the outside of the multilayerwiring board, so that the end face of the other resin layers 2 and 3 isprotected. By this composition, it is possible to prevent the damage atthe time of the cutting process from reaching the resin end face, andthe reliability can be improved.

Moreover, in the multilayer wiring board 10 of FIG. 2B, the fourth resinlayer 4 which is formed to be continuous with the outside resin layer 1among the resin layers 1-4 of each wiring board has a raised portion inthe cutting area 9 between the two wiring boards, and this raisedportion is covers an end face of the other resin layers 2 and 3 amongthe plurality of resin layers 1-4. And only the first resin layer 1 iscut at the raised portion to produce the two wiring boards, and theother resin layers 2 and 3 among the plurality of resin layers 1-4 areformed so that they are evacuated from the cutting area 9, respectively.

In the embodiment of FIG. 2A and FIG. 2B, the thickness of each of theresin layers 1-4 is about 4-6 micrometers, and the thickness of each ofthe wiring layers 5-8 is about 3-8 micrometers. The resin layers 1-4 aremade of any of a polyimide resin, a phenol resin, an epoxy resin, asilicon-based resin and BCB, and the wiring layers 5-8 are made of anyof Cu, Ni and Au, solely or in combination.

In the embodiment of FIG. 2A and FIG. 2B, the distance from the outsidesurface near the cutting area 9 of the resin layer 4 to the end face ofthe resin layers 2 and 3 is about 10-30 micrometers. However, when theadhesion force of the resin layers to be used is extremely weak, inorder to achieve a level of strength, the distance of this portion maybe set to about 100 micrometers.

FIG. 3 shows the composition of a modification of the multilayer wiringboard of FIG. 1A.

In the embodiment of FIG. 3, the fourth resin layer 4 is used in thecutting area 9 which will be cut at a next step, the end face of theother resin layers 1-3 is covered with the raised portion of the fourthresin layer 4, and it is possible to reduce the damage at the time ofcutting more effectively. In connection with this, the reliability ofthe multilayer wiring board is also improved. The end face of the resinlayers 1-3 for which the laminated formation is performed is coveredwith the raised portion of the fourth resin layer 4, and it is possibleto realize a compact interposer board without the damage and withoutlowering the reliability.

Moreover, in the multilayer wiring board 10 of FIG. 3, the fourth resinlayer 4 which is formed to be continuous with the outside resin layer 1among the resin layers 1-4 of one of the two wiring boards has a raisedportion in the cutting area 9 between the two wiring boards, and thisraised portion is flush with the outside resin layer 1 among the resinlayers 1-4 of the other of the two wiring boards.

In the embodiment of FIG. 3, the thickness of each of the resin layers1-4 is about 4-6 micrometers, and the thickness of each of the wiringlayers 5-8 is about 3-8 micrometers. The resin layers 1-4 are made ofany of a polyimide resin, a phenol resin, an epoxy resin, asilicon-based resin and BCB, and the wiring layers 5-8 are made of anyof Cu, Ni and Au, solely or in combination.

FIG. 4A and FIG. 4B show the composition of a multilayer wiring board inanother embodiment of the present invention.

In the embodiment of FIG. 4A and FIG. 4B, the isolated areas 1A whichare weaker than the structure of the interposer board in strength areformed in the region near the upper surface of the resin layer 2 (or 4)which will be cut as the crumple zone. By this composition, the damageat the time of cutting can be absorbed with the isolated areas 1A, andthe damage to the interposer board can be reduced.

In the embodiment of FIG. 4A, the isolated areas 1A are formed in thesecond resin layer 2 by using the resin material of the first resinlayer 1. When cutting the second resin layer 2, the portion of theisolated areas 1A serves as the crumple zone 9A, and it is possible toreduce the damage to the portion outside the isolated areas 1A.

In the embodiment of FIG. 4B, the isolated areas 1A are formed in thefourth resin layer 4 by using the resin material of the first resinlayer 1. When cutting the fourth resin layer 4, the portion of theisolated areas 1A serves as the crumple zone 9A, and it is possible toreduce the damage to the portion outside the isolated areas 1A.

The size and distance of the isolated areas 1A are usually about 10-30micrometers, respectively. It is better to set up the size and distancefor every resin layer since the optimum value for every resin variesaccording to the kind of the resin.

Also in this embodiment, the thickness of each of the resin layers isabout 4-6 micrometers, and the thickness of each of the wiring layers isabout 3-8 micrometers. The resin layers are made of any of a polyimideresin, a phenol resin, an epoxy resin, a silicon-based resin and BCB,and the wiring layers are made of any of Cu, Ni and Au, solely or incombination.

FIG. 5A through FIG. 5E show the composition of modifications of themultilayer wiring board of FIG. 4A.

In the embodiments of FIG. 5A through FIG. 5E, the size of the isolatedareas 1A is the same as that of the embodiment of FIG. 4A.

However, unlike the embodiment of FIG. 4A, the isolated areas 1A are notcovered with the continuous resin layer. For this reason, the externalforce at the time of mechanical cutting can be distributed moreeffectively.

It is also effective to form the isolated areas for every resin layer,and to form the crumple zone 9A, as shown in FIG. 5C, FIG. 5D and FIG.5E.

Also in the embodiment of FIG. 5A to FIG. 5E, the thickness of each ofthe resin layers 1-4 is about 4-6 micrometers, and the thickness of eachof the wiring layers 5-8 is about 3-8 micrometers. The resin layers 1-4are made of any of a polyimide resin, a phenol resin, an epoxy resin, asilicon-based resin and BCB, and the wiring layers 5-8 are made of anyof Cu, Ni, and Au, solely or in combination.

FIG. 6A and FIG. 6B show the composition of the multilayer wiring boardin another embodiment of the present invention. FIG. 7A and FIG. 7B showthe composition of modifications of the multilayer wiring board of FIG.6A.

In the present embodiment, the end face of the other resin layers 2-4other than the resin layer 1 which will be cut at a next step is coveredwith the metal film 11, and it is possible to raise the reliability ofthe multilayer wiring board more.

It is possible to strengthen the cross section more firmly according tothe anchor effect by forming the metal films 11, 12, and 13 to cover theend face of each of the resin layers 2, 3 and 4, respectively.

Also in the embodiment of FIG. 6A to FIG. 7B, the thickness of each ofthe resin layers 1-4 is about 4-6 micrometers, and the thickness of eachof the wiring layers 5-8 is about 3-8 micrometers. The resin layers 1-4are made of any of a polyimide resin, a phenol resin, an epoxy resin, asilicon-based resin and BCB, and the wiring layers 5-8 are made of anyof Cu, Ni and Au, solely or in combination.

FIG. 8A and FIG. 8B show the composition of a modification of themultilayer wiring board of FIG. 6A. FIG. 8A is a cross-sectional view ofthe multilayer wiring board of the present embodiment, and FIG. 8B is atop view of the portion of the multilayer wiring board indicated by thedotted line A in FIG. 8A.

In the present embodiment, the end face of the resin layers 2-4 otherthan the resin layer 1 is covered with the metal film 14, and this metalfilm 14 is connected with the metal film 13 formed on the resin layer 1.Thus, the end face of the resin layers 2-4 is protected more firmly, andthe adhesion force of the metal film 13 is also raised.

By this composition, the peripheral part of the resin layers 2-4 will bereinforced with the metal film 13, and the reliability is improved more.

Also in the embodiment of FIG. 8A, the thickness of each of the resinlayers 1-4 is about 4-6 micrometers, and the thickness of each of thewiring layers 5-8 is about 3-8 micrometers. The resin layers 1-4 aremade of any of a polyimide resin, a phenol resin, an epoxy resin, asilicon resin and BCB, and the wiring layers 5-8 are made of any of Cu,Ni and Au, solely or in combination.

FIG. 9 shows the composition of a modification of the multilayer wiringboard of FIG. 8A.

In the embodiment of FIG. 9, the metal film 13 is formed for coveringthe peripheral part of the resin layers 2-4, and this metal film 13 isconnected to the ground wiring 15 of each resin layer The electricalproperties can be improved by the composition of the multilayer wiringboard of FIG. 9.

Also in the composition of the embodiment of FIG. 9, the thickness ofeach of the resin layers 1-4 is about 4-6 micrometers, and the thicknessof each of the wiring layers 5-8 is about 3-8 micrometers. The resinlayers 1-4 are made of any of a polyimide resin, a phenol resin, anepoxy resin, a silicon-based resin and BCB, and the wiring layers 5-8are made of any of Cu, Ni and Au, solely or in combination.

FIG. 10A and FIG. 10B show the composition of the multilayer wiringboard in another embodiment of the present invention.

In the embodiment of FIG. 10A, the second resin layer 2 which will becut at a next process is thinly formed (the concave portion 2A). It ispossible to cut the thinly formed second resin layer 2 by a smallercutting force, and the damage to the interposer board can be reducedfurther.

The depth of the concave portion 2A formed in the cutting area 9 in thesecond resin layer 2 is about 1-4 micrometers, and the thickness of thesecond resin layer 2 of this portion is above 1-3 micrometers.

In the embodiment of FIG. 10B, the second resin layer 2 which will becut at a next process is thinly formed (the concave portion 2A), and themetal part of the cutting area 9 in the first wiring layer 5 is removedby the etching process (the metal removing part 5A). It is possible tocut the thinly formed second resin layer 2 by a smaller cutting force,and the damage to the interposer board can be reduced further.

The depth of the concave portion 2A formed in the cutting area 9 in thesecond resin layer 2 is about 1-4 micrometers, and the thickness of thesecond resin layer 2 of this portion is about 1-3 micrometers.

Also in the embodiment of FIG. 10A and FIG. 10B, the thickness of eachof the resin layers 1-4 is about 4-6 micrometers, and the thickness ofeach of the wiring layers 5-8 is about 3-8 micrometers. The resin layers1-4 are made of any of a polyimide resin, a phenol resin, an epoxyresin, a silicon-based resin and BCB, and the wiring layers 5-8 are madeof any of Cu, Ni and Au, solely or in combination.

FIG. 11A through FIG. 11E are diagrams for explaining the manufacturingmethod of the multilayer wiring board concerning the embodiment of FIG.1A.

In the present embodiment, as shown in FIG. 11A, after the first wiringlayer 5 is formed on the supporting board 17, the first resin layer 1 isformed. The via (not illustrated) for connecting electrically the firstwiring layer 5 and the second wiring layer 6 is formed in the firstresin layer 1.

As shown in FIG. 11B, the second wiring layer 6 is formed on the firstresin layer 1. And as shown in FIG. 11C, the second resin layer 2 isformed on the first resin layer 1 and the second wiring layer 6.

At this time, the second resin layer 2 is formed so that it is evacuatesfrom the cutting area 9 which will be cut at a next process.

As shown in FIG. 11D, the third and fourth wiring layers 7 and 8 and thethird and fourth resin layers 3 and 4 are formed similarly.

As shown in FIG. 11A, the first resin layer 1 and the first wiring layer5 are formed on the supporting board 17 which is made of silicon (Si).In this case, a silicon wafer is used. In this embodiment, the resinlayers 1-4 are formed using the polyimide resin 1-8150G from AsahiChemical Co.

Each resin layer is formed into a thin film which is about 5-6micrometers thick after resin curing. Since the above-mentionedpolyimide resin is photosensitive polyimide resin, when forming thesecond through fourth resin layers 2-4 and making them being evacuatedfrom the cutting area 9, they can be formed by performing thephoto-lithography process.

Specifically, after the above-mentioned polyimide resin is applied, itis exposed to the light exposure of about 500 mJ using the g-linesteppers, such as TITAN from ULTRATEC Co. Then, the development andrinsing are performed using the developing solution A-430 and therinsing solution C-260 from KURARIANTO JAPAN Co. At this time, the viafor electrically connecting the respective wiring layers is also formedsimultaneously.

After each resin layer is formed, a wiring layer is formed on the resinlayer. For example, the case where each wiring layer is formed using theelectrolytic plating method will be explained.

On the resin layer, an electric supply layer is formed by the sputteringprocess. In the case of this embodiment, titanium (Ti) and Cu are formedby a thickness of 100 nm and 250 nm, respectively.

After the sputtering process, the patterning is performed with thephotoresist. For example, the posi-resist LA900 from TOKYO OHKA KOGYO Cois used as the photoresist, and the exposure of about 1000 mJ isperformed by using the g-line stepper.

Similarly, the development is performed using the developing solutionP-7 from TOKYO OHKA KOGYO Co., and the pattern is formed. After thepattern is formed, the electrolytic plating is performed to form thewiring layer.

The first through fourth wiring layers 1-4 are made of any of Cu, Ni andAu, solely or in combination. In this embodiment, the first wiring layer1 is made of Ni/Au, the second and third wiring layers 2 and 3 are madeof Cu, and the fourth wiring layer 4 is made of Cu/Ni/Au, respectively.

Next, the formation method of the second and third wiring layers 2 and 3will be explained.

For example, the plated Cu layer is formed in a thickness of about 3micrometers using CU300 from EEJA Co. The etching process to remove theelectric supply layer is performed after the plating formation. Anacetic peroxide and a hydrofluoric acid are used for the etching processof Cu and Ti, respectively. As for other wiring layers, the platingmaterial is changed suitably and the wiring layers are formed similarly.

As shown in FIG. 11E, after all the resin layers 1-4 and the wiringlayers 5-8 are formed, the supporting board 17 is removed. In this case,the removal of the Si substrate can be easily performed in such a mannerthat, after the supporting board 17 is thinned to a thickness of about50 micrometers using a grinding machine, the thinned board is dissolvedwith a mixed acid of a hydrofluoric acid and a nitric acid.

By using the above-mentioned manufacturing method of FIG. 11A to FIG.11E, it is possible to form easily the multilayer wiring board 10 inwhich the resin layers 2-4 are evacuated from the cutting area 9,without performing a special process.

FIG. 12A through FIG. 12E are diagrams for explaining the manufacturingmethod of the multilayer wiring board in the embodiment of FIG. 2A.

In this embodiment, as shown in FIG. 12A, after forming the first wiringlayer 5 on the supporting board 17, the first resin layer 1 is formed.The via (not illustrated) for connecting electrically the first wiringlayer 5 and the second wiring layer 6 is formed in the first resin layer1.

As shown in FIG. 12B, the second wiring layer 6 is formed on the firstresin layer 1.

And as shown in FIG. 12C, the second resin layer 2 is formed on thefirst resin layer 1 and the second wiring layer 6.

At this time, the second resin layer 2 is formed so that it is evacuatedfrom the cutting area 9 which will be cut at a next process.

As shown in FIG. 12C, the third wiring layer 7, the third resin layer 3,and the fourth wiring layer 8 are formed similarly.

As shown in FIG. 12D, the fourth resin layer 4 is formed so that thesecond and third resin layers 2 and 3 are covered with the fourth resinlayer 4. Only the first resin layer 1 and the fourth resin layer 4 areexposed to the outside of the multilayer wiring board 10.

As shown in FIG. 12E, after the fourth resin layer 4 is formed, thesupporting board 17 is removed.

The detailed composition of this embodiment is essentially the same asthat of the above-described embodiment of FIG. 11E. According to themanufacturing method of this embodiment, it is possible to easily formthe multilayer wiring board 10 in which only the top resin layer 1 andthe bottom resin layer 4 among the plurality of resin layers are exposedto the outside.

FIG. 13A through FIG. 13E are diagrams for explaining the manufacturingmethod of the multilayer wiring board in the embodiment of FIG. 3.

In this embodiment, as shown in FIG. 13A, the first resin layer 1 isformed on the supporting board 17, so that it is evacuated from thecutting area 9 which will be cut at a next process.

As shown in FIG. 13B and FIG. 13C, after the first wiring layer 5 isformed on the first resin layer 1, the laminated formation is similarlycarried out for the second through fourth wiring layers 6 to 8.

As shown in FIG. 13D, after the fourth wiring layer 8 is formed, thefourth resin layer 4 is formed so that the end face of the first throughthird resin layers 1-3 is covered with the fourth resin layer 4.

After the fourth resin layer 4 is formed, as shown in FIG. 13E, thesupporting board 17 is removed.

The detailed composition of this embodiment is essentially the same asthat of the above-described embodiment of FIG. 11E. According to themanufacturing method of this embodiment, it is possible to form easilythe multilayer wiring board 10 in which the end face of the resin layers1-3 which are evacuated from the cutting area 9 is covered with thesingle resin layer 4 which will be cut.

FIG. 14A through FIG. 14D are diagrams for explaining the manufacturingmethod of the multilayer wiring board in the embodiment of FIG. 4A.

In this embodiment, as shown in FIG. 14A, the first resin layer 1 isformed on the supporting board 17, so that it is evacuated from thecutting area 9A which will be cut at a next process. And the twoisolated areas 1A are formed so that they are separately arranged in thecutting area 9A.

Then, as shown in FIG. 14B, the second wiring layer 6 is formed on thefirst resin layer 1 so that it is connected with the first wiring layer5.

After the second wiring layer 6 is formed, the second resin layer 2 isformed. The second resin layer 2 is formed so that all the cutting area9 (which will be cut at a next process), the first resin layer 1 and thesecond wiring layer 6 are covered with the second resin layer 2. Namely,only the second resin layer 2 is made continuous between the right andleft wiring boards which are produced by cutting the multilayer wiringboard.

Then, as shown in FIG. 14C, the third and fourth wiring layers 7 and 8and the third and fourth resin layers 3 and 4 are formed, respectively.

Finally, as shown in FIG. 14D, the supporting board 17 is removed. Thethird and fourth resin layers 3 and 4 are formed so that they areevacuated from the cutting area 9A which will be cut at a next process.

The detailed composition of this embodiment is essentially the same asthat of the above-described embodiment of FIG. 11E. By using thismanufacturing method, it is possible to form the isolated area 1Asimultaneously at the time of formation of the first resin layer 1, andit is possible to form easily the multilayer wiring board 10 in whichthe crumple zone 9A is provided.

FIG. 15A through FIG. 15D are diagrams for explaining the manufacturingmethod of the multilayer wiring board in the embodiment of FIG. 5A.

In this embodiment, as shown in FIG. 15A, the first resin layer 1 isformed on the supporting board 17, so that it is evacuated from thecutting area 9A which will be cut at a next process. And the twoisolated areas 1A are formed so that they are separately arranged in thecutting area 9A.

Then, as shown in FIG. 15B, the second wiring layer 6 is formed on thefirst resin layer 1 so that it is connected with the first wiring layer5. After the second wiring layer 6 is formed, the second resin layer 2is formed. The second resin layer 2 is formed and separately arranged onthe isolated area 1A which is arranged at the time of formation of thefirst resin layer 1 and the area thereof is made small.

Then, as shown in FIG. 15C, the third and fourth wiring layers 7 and 8and the third and fourth resin layers 3 and 4 are formed, respectively.

Finally, as shown in FIG. 15D, the supporting board 17 is removed. Thethird and fourth resin layers 3 and 4 are formed so that they areevacuated from the cutting area 9A which will be cut at a next process.

Similar to the above-mentioned embodiment of FIG. 14D, it is possible toform easily the multilayer wiring board 10 in which the more effectivecrumple zone 9A is arranged, by performing the manufacturing method ofFIG. 15A to FIG. 15D.

FIG. 16A through FIG. 16D are diagrams for explaining the manufacturingmethod of the multilayer wiring board in the embodiment of FIG. 6A.

In this embodiment, as shown in FIG. 16A, the first wiring layer 5 andthe first resin layer 1 are formed on the supporting board 17.

As shown in FIG. 16B, after the second wiring layer 6 is formed on thefirst resin layer 1, the second resin layer 2 is formed so that it isevacuated from the isolated area 9 which will be divided at a nextprocess.

The third wiring layer 7 and the third resin layer 3 are formedsimilarly. After the third resin layer 3 is formed, the fourth wiringlayer 8 is formed. At this time, as shown in FIG. 16C, the metal film 11is simultaneously formed so that the end face of the second and thirdresin layers 2 and 3 is covered with the metal film 11.

Then, as shown in FIG. 16D, the fourth resin layer 4 is formed, and thesupporting board 17 is removed. In the present embodiment, the materialand thickness of each wiring layer is as follows. The first wiring layer5 is: Ni/Au/Ni=0.1 micrometers/0.5 micrometers/3.5 micrometers. Thesecond and third wiring layers 6 and 7 are: Cu=3 micrometers. The fourthwiring layer 8 is: Cu/Ni/Au=3 micrometers/3.5 micrometers/0.2micrometers.

The detailed composition of this embodiment is essentially the same asthat of the above-mentioned embodiment of FIG. 11E. In this embodiment,the metal film 11 covering the end face of the second and third resinlayers 2 and 3 is formed simultaneously with formation of the fourthwiring layer 8, and it is possible to form easily the multilayer wiringboard 10 in which the metal film 11 is formed, without increasing anadditional process.

FIG. 17A through FIG. 17D are diagrams for explaining the manufacturingmethod of the multilayer wiring board in the embodiment of FIG. 7A.

In this embodiment, as shown in FIG. 17A, the first wiring layer 5 andthe first resin layer 1 are formed on the supporting board 17.

After the second wiring layer 6 is formed, the second resin layer 2 isformed so that it is evacuated from the isolated area 9 which will becut at a next process. The third wiring layer 7 and the third resinlayer 3 are also formed similarly.

As shown in FIG. 17B, after the third resin layer 3 is formed, thefourth wiring layer 8 is formed. At this time, as shown in FIG. 17B, themetal film 11 is formed so that the end face of the second and thirdresin layers 2 and 3 is covered with the metal film 11.

Then, as shown in FIG. 17C, the fourth resin layer 4 is formed. Afterthe fourth resin layer 4 is formed, the second metal film 12 is formedso that it covers the end face of the fourth resin layer 4 and isconnected to the metal film 11 which covers the end face of the secondand third resin layers 2 and 3.

As shown in FIG. 17D, after the second metal film 12 is formed, thesupporting board 17 is removed.

The detailed composition of this embodiment is essentially the same asthat of the above-described embodiment of FIG. 11E. By using thismanufacturing method, it is possible to form easily the multilayerwiring board 10 in which the metal films 11 and 12 are formed.

FIG. 18A through FIG. 18D are diagrams for explaining the manufacturingmethod of the multilayer wiring board in the embodiment of FIG. 8A.

In this embodiment, as shown in FIG. 18A, the first wiring layer 5 andthe first resin layer 1 are formed on the supporting board 17. Thesecond wiring layer 6 is formed on the first resin layer 1. The secondresin layer 2 is evacuates from the cutting area 9 which will be cut ata next process. The third wiring layer 7 is formed and the third resinlayer 3 is formed like the second resin layer 2.

The via 19 which is connected to the first wiring layer 5 is formed inthe second and third resin layers 2 and 3. The fourth wiring layer 8 isformed and the fourth resin layer 4 is formed.

As shown in FIG. 18B, the via 19, which is connected to the first wiringlayer 5 and penetrates the second through fourth resin layers 2-4, isformed also in the fourth resin layer 4.

After the fourth resin layer 4 is formed, as shown in FIG. 18C, themetal film 14 is formed so that it is connected to the first wiringlayer 5 through the via 19, and that the end face of the second throughfourth resin layers 2-4 is covered with the metal film 14. Then, asshown in FIG. 18D, the supporting board 17 is removed.

The detailed composition of this embodiment is essentially the same asthat of the above-described embodiment of FIG. 11E. In the multilayerwiring board 10 of this embodiment, in order to connect the metal film14 covering the end face of the second through fourth resin layers 2-4,and the first wiring layer 5, the via 19 is formed in the second throughfourth resin layers 2-4.

By using the above-mentioned photosensitive polyimide resin, the via 19can be formed easily. Thus, it is possible to form easily the multilayerwiring board 10 of this embodiment by using the manufacturing method ofFIG. 18A through FIG. 18D.

FIG. 19A through FIG. 19D are diagrams for explaining the manufacturingmethod of the multilayer wiring board in the embodiment of FIG. 9A.

In this embodiment, as shown in FIG. 19A, the first wiring layer 5 andthe first resin layer 1 are formed on the supporting board 17.

The second wiring layer 6 is formed on the first resin layer 1. Thesecond resin layer 2 is formed so that it is evacuates from the cuttingarea 9 which will be cut at a next process.

Moreover, the third wiring layer 7 is formed and the third resin layer 3is formed like the second resin layer 2. The via 19 which is connectedto the first wiring layer 5 is formed in the second and third resinlayers 2 and 3. The fourth wiring layer 8 is formed and the fourth resinlayer 4 is formed.

As shown in FIG. 19B, the via 19 which is connected to the first wiringlayer 5 and penetrates the second through fourth resin layers 2-4 isformed also in the fourth resin layer 4.

The ground wiring 15 of the second and third wiring layers 6 and 7 isconnected to the via 19 respectively, and this via 19 is formed so thatit penetrates the second through fourth resin layers 2-4.

After the fourth resin layer is formed, as shown in FIG. 19C, the metalfilm 14 is formed so that it is connected to the first wiring layer 5through the via 19 and connected to the ground wiring 15 of the secondand third wiring layers 6 and 7, and the end face of the second throughfourth resin layers 2-4 is covered with the metal film 14. Then, asshown in FIG. 19D, the supporting board 17 is removed.

The detailed composition of this embodiment is essentially the same asthat of the above-described embodiment of FIG. 18D. The multilayerwiring board 10 of this embodiment is formed so that the ground wiringof each wiring layer is exposed to the via 19 formed in each resinlayer, in order to connect the metal film 14 covering the end face ofthe second through fourth resin layers 2-4, and the ground wiring 15 ofthe first wiring layer 5.

The photo-lithography process can be performed for the formation of themetal film 14 simultaneously with the formation of each wiring layer andeach resin layer, and it is possible for the manufacturing method ofthis embodiment to form easily the multilayer wiring board 10.

FIG. 20A through FIG. 20D are diagrams for explaining the manufacturingmethod of the multilayer wiring board in the embodiment of FIG. 10A.

In this embodiment, as shown in FIG. 20A, when forming the first wiringlayer 5 on the supporting board 17, a metal film is simultaneouslyformed also in the cutting area 9 which will be cut at a next step.

Then, as shown in FIG. 20B and FIG. 20C, the first resin layer 1 throughthe fourth wiring layer 8 are formed one by one by performing any of theabove-mentioned methods.

As shown in FIG. 20D, the metal film formed in the cutting area 9 isremoved simultaneously in the process which is performed to remove thesupporting board 17.

The detailed composition of this embodiment is essentially the same asthat of the above-mentioned embodiment of FIG. 11E. The metal filmformed in the cutting area 9 is formed simultaneously with the formationof the first wiring layer 5. In order to prevent the metal film frombeing removed the etching process performed at the time of removal ofthe supporting board 17, the metal material which forms the first wiringlayer 5 and serves as a stopper metal is arranged so that it issandwiched between the first resin layer 1 and the second resin layer 2.

At this time, the metal which serves as a stopper metal is formed bymaking the size of the via formed in the first resin layer 1 smallerthan the size of the via formed in the second resin layer 2.

In the metal part 5A formed in the cutting area 9, the via of the firstresin layer 1 and the via of the second resin layer 2 are formed in thesame size. By forming in this way, at the time of the etching process toremove of the supporting board 17, the etchant is turned around thestopper metal, and it is possible to remove the metal film thoroughly.By using the manufacturing method of FIG. 20A through FIG. 20D, it ispossible to easily form the multilayer wiring board 10 of thisembodiment.

FIG. 21A, FIG. 21B, FIG. 21C and FIG. 21D show the composition of theinterposer boards which are produced by cutting the multilayer wiringboards of FIG. 1A, FIG. 1B, FIG. 2A and FIG. 3, respectively.

In the embodiments of FIG. 21A to FIG. 21D, the cutting area 9 is formedonly by a single resin layer, and almost no mechanical damage is foundin the cutting plane of the multilayer wiring board 10 at the time ofcutting the resin layer. It is possible to provide an interposer boardwith good reliability.

In the interposer boards shown in FIG. 21C and FIG. 21D, the cuttingplane (end face) of the other resin layers is further covered with theresin layer, and the reliability can be raised.

The thickness of each of the resin layers 1-4 is about 4-6 micrometers,and the thickness of each of the wiring layers 5-8 is about 3-8micrometers. The resin layers 1-4 are made of any of a polyimide resin,a phenol resin, an epoxy resin, a silicon-based resin and BCB, and thewiring layers 5-8 are made of any of Cu, Ni and Au, solely or incombination.

FIG. 22A, FIG. 22B, FIG. 22C, FIG. 22D and FIG. 22E show the compositionof the interposer boards which are produced by cutting the multilayerwiring boards of FIG. 4A, FIG. 5B, FIG. 5C, FIG. 5D and FIG. 5E,respectively.

In this embodiment, the interposer board is configured so that thecrumple zone 9A is arranged in the peripheral part of the resin layerwhich is cut. It is possible to reduce the damage at the time of cuttingthe resin layer.

The thickness of each of the resin layers 1-4 is about 4-6 micrometers,and the thickness of each of the wiring layers 5-8 is about 3-8micrometers. The resin layers 1-4 are made of any of a polyimide resin,a phenol resin, an epoxy resin, a silicon-based resin and BCB, and thewiring layers 5-8 are made of any of Cu, Ni and Au, solely or incombination.

FIG. 23A and FIG. 23B show the composition of the interposer boardswhich are produced by cutting the multilayer wiring boards of FIG. 6Aand FIG. 6B, respectively.

In this embodiment, the resin end face of the peripheral part in thethus produced interposer board is covered with the metal film 11. It ispossible to provide a reliable interposer board by covering the end faceof the plurality of resin layers 2-4 with the metal film 11.

The thickness of each of the resin layers 1-4 is about 4-6 micrometers,and the thickness of each of the wiring layers 5-8 is about 3-8micrometers. The resin layers 1-4 are made of any of a polyimide resin,a phenol resin, an epoxy resin, a silicon-based resin and BCB, and thewiring layers 5-8 are made of any of Cu, Ni and Au, solely or incombination.

FIG. 24A and FIG. 24B show the composition of the interposer boardswhich are produced by cutting the multilayer wiring boards of FIG. 7Aand FIG. 7B, respectively.

In this embodiment, the metal films 11-13 are formed for the resin layer2-4 respectively, and the higher anchoring effect can be obtained and itis possible to provide an interposer board with higher reliability.

The thickness of each of the resin layers 1-4 is about 4-6 micrometers,and the thickness of each of the wiring layers 5-8 is about 3-8micrometers. The resin layers 1-4 are made of any of a polyimide resin,a phenol resin, an epoxy resin, a silicon-based resin and BCB, and thewiring layers 5-8 are made of any of Cu, Ni and Au, solely or incombination.

FIG. 25A, FIG. 25B and FIG. 25C show the composition of the interposerboards which are produced by cutting the multilayer wiring boards ofFIG. 8A, FIG. 8B and FIG. 9, respectively.

In the embodiment of FIG. 25A and FIG. 25B, a more reliable interposerboard can be provided by connecting the wiring layer 13 formed on thefirst resin layer 1 with the metal film 14 which protects the peripheralpart of the end face of the second through fourth resin layers 2-4.

In the embodiment of FIG. 25C, an interposer board with increasedelectrical properties can be provided by connecting the metal film 14 inthe circumferential part with the ground wiring 15 of each resin layer.

The thickness of each of the resin layers 1-4 is about 4-6 micrometers,and the thickness of each of the wiring layers 5-8 is about 3-8micrometers. The resin layers 1-4 are made of any of a polyimide resin,a phenol resin, an epoxy resin, a silicon-based resin and BCB, and thewiring layers 5-8 are made of any of Cu, Ni and Au, or solely or incombination.

According to the composition of the interposer board of this embodiment,the advantageous features which are the same as those of theabove-mentioned multilayer wiring boards of FIG. 8A, FIG. 8B and FIG. 9can be acquired.

The present invention is not limited to the above-described embodiments,and variations and modifications may be made without departing from thescope of the present invention.

1. A multilayer wiring board, comprising: a plurality of wiring boardsin which wiring layers and resin layers in each wiring board arealternately arranged in a laminated formation, wherein all the resinlayers and the wiring layers, except a predetermined resin layer in theplurality of wiring boards, are separated in a cutting area between theplurality of wiring boards, wherein the predetermined resin layer iscontinuous in the cutting area, wherein said predetermined resin layeris a first resin layer which is arranged in a lowermost position amongthe resin layers in each wiring board, and wherein the first resin layerin the cutting area is arranged in an uppermost position among saidresin layers and has a portion that covers an end face of at least oneof other resin layers in the plurality of wiring boards.